Attention: This service manual is only for service personnel to take reference with. Before servicing please read the following points carefully. Safety precautions 1. Instructions Be sure to switch off the power supply before replacing or welding any components inserting/plugging in connection wire Anti static measures to be taken (throughout the entire production process!): a) Do not touch here and there by hand at will;...
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would be unable to work and no way to get it repaired. If the connection wires, connectors or components fixed by the thermotropic glue need to disengage when service, please soak the thermotropic glue into the alcohol and then pull them out in case of dagame.
Alignment instructions 1. Test equipment PM5518 (video signal generator) VG-849 (VGA signal generator) CA210 (white balancer) 2 Alignment flow-chart The alignment flow-chart is shown as fig-1 Check DDC, HDCP KEY, FLASH and POWER control IC Combined test for general assembly Factory initialization setup IF channel voltage of TV and AGC voltage adjustment White balance adjustment...
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BACK LIGHT Adjust according different screen ALL COLOR 1: white balance of each channel auto offset based on the HDMI white balance 0: white balance of each channel adjust the offset base separately 0: no unit upgrade on the assembly line 1: unit upgrade on the assembly line NO STANDY 01: turn on;...
4 Software upgrade When software upgrading please enter factory menu first, enter ISP of OPTION, set ISP to 1 and you can begin to upgrade. After upgrade finished, it needs to set ISP back to 0. If the picture can’t display when upgrading, it needs to web J1 of 01S board.
Working principle analysis of the unit The RF signal received by antenna will be sent to tuner TUN401, then IF signal will be obtained through high amplifier and mixed frequency, through pre-intermediate amplified by V408, then it will be sent to acoustic surface-wave Z407 to do IF filter and get better IF characteristics, then it will be sent to N404 (TDA4470) to do intermediate amplification, phase-locked loop VCO and synchronous wave detection to get video signal TV-V;...
IC block diagram 1. MST9E88L The MST9E88L is a high performance and fully integrated IC for multi-function LCD monitor/TV with resolutions up to SXGA/WXGA. It is configured with an integrated triple-ADC/PLL, an integrated DVI/HDCP/HDMI receiver, a multi-standard TV video and audio decoder, a video de-interlacer, a scaling engine, the MStarACE-3 color engine, an on-screen display controller, an 8-bit MCU and a built-in output panel interface.
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2. MP7722DF The MP7722 is a stereo 20W Class D Audio Amplifier. It is one of MPS’second generation of fully integrated audio amplifiers which dramatically reduces solution size by integrating the following: 180mΩ power MOSFETs Startup / Shutdown pop elimination Short circuit protection Mute / Standby The MP7722 utilizes a single ended output structure capable of delivering 2 x 20W into 4Ωspeakers.
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3. TDA4470 The TDA4470 is an integrated bipolar circuit for multi-standard video/sound IF(VIF/SIF) signal processing in TV/VCR and multimedia applications. The circuit processed all TV video IF signals with negative modulation (e.g., B/G standard), positive modulation (e.g., L standard) and the AM, FM/NICAM sound IF signals.
Trouble shooting 1. Fault clearance Before servicing please check to find the possible causes of the troubles according to the table below. 1.1 Antenna (signal): Picture is out of focus or jumping Bad status in signal receiving Poor signal Check if there are failures with the electrical connector or the antenna.
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signal types. Picture too bright and there is Check if the contrast setting is too high. distortion in the brightest area Possibly the output quality of DVD broadcaster is set too high. It maybe also due to improper terminal connection of the video frequency signal in a certain position of the system.
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2. Identification criteria for the bright spot and dark spot of the LCD screen Quantity allowed Distance between two spots Category Criteria 15" 20" 22" 30" 40" 15" 20" 22" 30" 40" One single ≤5 ≤2 ≤5 ≤2 ≤3 spot Bright ≥15mm spot...
3. Troubleshooting guide 3.1. No raster Turn-on power supply, check if the red indicator is light in the STANDBY? Check if PIN3(5V) of main Press POWER button in the board is normal? unit or sensor control and check the indicator. blue Check if the PIN12 of X301 in Check STANDBY circuit of...
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3.2. Raster, but no picture Check if the unit button Does display remote control menu in screen when operation? press menu button? Check channels have signal? HDMI/VGA/YPRPB Enter factory-menu, Which is no signal initialization EEPROM, of channels Replace then turn off the TV, main board turn on again, display Replace...
3.3.no sound Check if PIN2, 8,13 and Check PIN3 18 voltage of N405 is PIN7 output wave of Check N405 and its normal? N405 periphery Check power supply Check PIN24 wave of Check NS4 and its N404 periphery Check N404 and its Check PIN11 wave of periphery TUNER401...
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APPENDIX-A: Main assembly LCD-26XR7 MAIN COMPONENT AND IT'S NO. NAME N404 TDA4470 (5274470001) Analog board XI6HU0495310 N405 MP7722DF (5277722001) Main board XI6HU07001S0 MST9E88 (5270988002) Interface board XI6HU0212910 Key board XI6HU0230510 IR receiver board XI6FW0050910 Power board XI6HU0162010 Remote control RC-Y35-0F...
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PART LIST OF EXPLODED VIEW (LCD-26XR7) DESCRIPTION Front cover Screen Power board Main board Key board Back cabinet Stand Speaker Analog board Trans-connecting board Power swtich Infrared receiving board User manual Remote Control...
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PARTS LIST LCD-26X R7 ver.1.0 R E F.No. PAR T S No. DE S C R IP T ION Q'T Y R E MAR K F ront C over XI5QX32W2010 Infrared R eceiving B oard XI6F W0050910 S creen C MO V 260B 1-L01 & L02 XI6HU07001S 0 Main B oard XI6HU0230510...
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PART LIST OF EXPLODED VIEW (LCD-32XR7) DESCRIPTION Front cover Infrared receiving board Screen Main board Key board Back cabinet Speaker Stand Trans-connecting board Analog board Power board Power swtich User manual Remote Control...
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PARTS LIST LCD-32X R7 ver.1.0 R E F.No. PAR T S No. DE S C R IP T ION Q'T Y R E MAR K F ront C over XI5QG 32W202A Infrared R eceiving B oard XI6F W0050910 S creen C MO V 320B 1-L04 XI6HU04901S 0 Main B oard...